Darwin Day: A personal offering

Two hundred and four years ago this day, Charles Darwin was born. The vision of life that he created and expounded on transformed humanity's perception of its place in the universe. After Copernicus's great heliocentric discovery, it was Darwin's exposition of evolution and natural selection that usurped human beings from their favored place at the center of the universe. But far from trivializing them, it taught them about the vastness and value of life, underscored the great web of interactions that they are a part of, and reinforced their place as both actor and spectator in the grand game of the cosmos. Not only as a guiding scientific principle but as an all-encompassing element of understanding our place in the world, evolution through natural selection has become the dominant idea of our time. As the eminent biologist Theodosius Dobzhansky put it quite simply, nothing in biology makes sense except in the light of evolution. Evolution is a fact. Natural selection is a theory that is now as good as a fact. Both evolution and natural selection happen. And both of them owe their exalted place in our consciousness to a quiet, gentle and brilliant Englishman.

Today it is gratifying and redeeming to know how right Darwin was and how much his theory has been built upon, and frustrating to keep on realizing how those professing religious certainty threaten to undermine the value of his and others' careful and patient discoveries. Especially in the United States evolution has become a bizarre battleground of extreme opinions and mudslinging, a development that seems to be in step with the tradition of coloring any and every issue with a political hue. In this country, it seems today that you can hardly utter an opinion without attaching a label to it. You cannot simply have an opinion or take a position, no matter how grounded in fact it is; your position has to be Republican, Democrat, Libertarian, Neo-Conservative, Socialist or Atheist. if none of these, it has to be Centrist then.

When it comes to evolution, attaching the label of "Darwinism" has obscured the importance and power of the theory of natural selection. On one hand, those who defend the label sometimes make it sound as if Darwin was the beginning and end of everything to do with evolution. This is simply untrue; in his creation of the theory of natural selection, Darwin was a little like Martin Luther King. The Civil Rights movement owed an incalculable debt to King, but King was not the Civil Rights movement. On the other hand, those who oppose the Darwinist label make it sound like all of us who "believe" in evolution and natural selection have formed a cult and get together every weekend to worship some Darwin idol.

Unfortunately both these positions only serve to obfuscate the life and times of the man himself, a simple, gentle and brilliant soul who painfully struggled with reconciling his view of the world with prevailing religious sentiments and who thought it right to cast his religious views aside in the end for the simple reason that his findings agreed with the evidence while the others did not. Darwin Day should be a chance to celebrate the life of this remarkable individual, free from the burdens of religion and political context that his theory is embroiled in today. Because so much has been said and written about Darwin already, this will be more of a personal and selective exposition. Since I am a lover of both Darwin and books, I will tell my short story of Darwin as I discovered him through books.

When you read about his life for the first time, Charles Darwin does not evoke the label of "genius", and this superficial incongruence continues to beguile and amaze. His famous later photographs show a bearded face with deeply set eyes. His look is gloomy and boring and is not one which elicits the image of a sparkling, world-changing intellect and incendiary revolutionary taking on an establishment steeped in dogma. Darwin was not a prodigy by the standards of William Hamilton or Lord Kelvin, nor did he particularly excel in school and college. A Cambridge man who studied religion, Darwin had one overriding quality; curiosity about the natural world. He consummately nurtured this quality in field trips and excursions; as one famous story goes, Darwin once held two beetles in two hands and popped one of them in his mouth so that he could free one hand for catching a third very attractive one which he had just noticed. He indulged in these interests much to the chagrin of his father who once said that he would not amount to anything and that he would be a disgrace to his family.

As is well-known, Darwin's story really begins with his voyage of the Beagle when he accepted a position on a ship whose melancholic, manic-depressive captain Robert Fitzroy wanted an educated, cultured man to keep him company on a long and dangerous voyage that circumnavigated the world. For Darwin this was a golden chance to observe and document the world's flora and fauna. One of the best illustrated expositions of Darwin's voyage is in Alan Moorhead's "The Voyage of the Beagle" which is beautifully illustrated with original drawings of the wondrous plants, animals and geological formations that Darwin saw on the voyage. Darwin's own account of the voyage is characteristically detailed and modest and depicts a man enthralled by the beauty of the natural world around him. By the time he set off on his historic journey, young Charles had already been inspired by his teacher Charles Lyell's book on geology that talked about geological changes over vast tracts of time. As is also rather well-known, evolutionary ideas had been in the air for quite some time by then (as marvelously documented in Rebecca Stott's recent book "Darwin's Ghosts"), and Darwin certainly was not the first to note the rather simple fact that organisms seem to have changed over time, a view that nonetheless and naturally flew in the face of religious dogma. Most importantly, Darwin was well-aware of Thomas Malthus's famous argument about the proliferation of species exceeding the resources available to them, an idea whose logical extension would be to conjecture a kind of competition between species and individuals for finite resources. The "struggle for survival", taught today in school textbooks, a phrase that became much maligned later, nonetheless would have been obvious to a man as intelligent and perceptive as Darwin when he set off on his voyage.

Biology, unlike mathematics or physics, is a science more akin to astronomy that relies on extensive tabulation and observation. Unlike a theoretical physicist, a biologist would be hard-pressed to divine truths about the world by armchair speculation. Thus, painstakingly collecting and classifying natural flora and fauna and making sense of its similarities and differences is a sine qua non of the biological sciences. Fortunately Darwin was the right man in the right place; endowed with a naturally curious mind with an excellent memory for assimilation and integration, he was also unique and fortunate to embark on a worldwide voyage that would enable him to put his outstanding faculties to optimum use. Everywhere he went he recorded meticulous details of geology, biology, anthropology and culture. His observation of earthquakes and rock formations in South America and his finding of fossils of giant mammals lend credence to his beliefs about organisms being born and getting extinguished by sometimes violent physical and planetary change. His observation of the Pacific and Atlantic islanders (especially the ones on Tierra del Fuego) and their peculiar customs underscored the diversity of human life along with other life in his mind. But perhaps his best known and most important stop came after several months of traveling, when the ship left Ecuador to dock at the Galapagos Islands.

Again, much has been written about the Galapagos Islands and about Darwin's Finches. The truth is more subtle, sometimes simpler and sometimes more interesting than what it is made out to be. Darwin had mistaken his famous finches for other species of birds. It was only after coming back that his friend, the ornithologist John Gould, helped him to identify their correct lineage. But finches or not, the birds and the islands provided Darwin with a unique opportunity to study what we now know as natural selection. The islands were separated from each other by relatively small distances and yet differed significantly in their geography and flora and fauna. On each island Darwin observed similar plants and animals that were yet distinct from each other. As in other places, he also observed that species seemed to be adapted to their environment. Geographic isolation and speciation were prominent on those hot, sweaty and incredibly diverse land masses.

After five years of exhaustive documentation and sailing Darwin finally returned home for good, much changed both in physical appearance and belief. His following life has been the subject of much psychological speculation since he settled down with his cousin Emma and never ever left the British Isles again. He also seemed to have been stricken with what today is noted by many authors as a kind of psychosomatic illness because of which he was constantly ill with abdominal and other kinds of pains. After living in London for some time, Darwin retired to Down's House in Kent where he peacefully lived the rest of his life with a kind and loving wife, playing with his children, taking walks along the path at the back of his house named the "Sandwalk", corresponding with intellectuals around the world and constantly interrupting his research with salutary visits to spas and resorts for "natural" treatments that were sometimes of dubious value.

But peaceful as his life was, psychologically Charles Darwin was fomenting a maelstrom of revolution that was to have earth-shaking implications. Another fact that is frequently emphasized is his hesitation to not publish his ideas for another twenty five years in the form of the famous "The Origin of Species". Darwin was planning to write it for a while, but was finally jolted into writing it when he received a letter from an obscure young naturalist named Alfred Russell Wallace who was living a hard life of science and natural history exploration in Indonesia. Wallace had read some of Mr. Darwin's papers and manuscripts and had been struck by the similarity of his ideas to his own. Would Mr. Darwin comment on them? Darwin finally realized that he had to act to prevent getting scooped but characteristically credited Wallace in his published work.

In my mind however, Darwin's procrastination and its story sounds much simpler than the mystique and psychological speculation that sometimes envelop it. As we noted earlier, Darwin was a highly trained biologist and scientist of the first caliber. He knew that he would have to exhaustively document and classify the windfall of creatures, plant and rock specimens that he had collected on his voyage. Apart from thinking and writing about his Beagle collections, Darwin also maintained an astonishingly comprehensive and detailed research program on marine invertebrates and barnacles. More tellingly, he did experiments to find out if seeds are viable even when dispersed over long distances over salt-water. He visited gardens and zoos, and quizzed pigeon breeders about their profession. Much of this was in preparation for the grand act that was to follow. In case of the barnacles and marine creatures, Darwin's research was second to none. He published several extremely detailed books on the minutiae of these organisms; some of these had titles which would have put anyone to sleep. And yet the level of detail in them reflects the extraordinary patience, power of observation and meticulous hard work that characterized the man, characteristics crucial for developing the theory of natural selection. Darwin was also very fortunate to have had several friends and colleagues who were experts in areas that he was not, who helped him classify and name all the material. Foremost among his correspondents were Charles Lyell and Joseph Hooker to whom he confided not just his scientific questions but also his emerging convictions about the interconnections and implications that were emerging from his research and writing. Also as noted above, John Gould accomplished the crucial task of reminding Darwin that his Galapagos birds were finches. With help from these collaborators and his own studies and thoughts on his observations, thoughts that filled literally dozens of rough drafts, scribblings and private diaries, Darwin finally began to glimpse the formation of a revolutionary chain of thought in his mind.

But Darwin did not rush forth to announce his ideas to the world, again for reasons that are obvious; Victorian England was a hotbed of controversy between science and religion, with many distinguished and famous scientists there and in other countries not just fervently believing in God, but writing elegant tomes that sought a supernatural explanation for the astounding diversity of life around us. Cambridge was filled with intellectuals who sought a rational framework for God's intervention. Darwin would have been quite aware of these controversies. Even though Darwin's grandfather (a more pugnacious character) himself had once propounded an evolutionary view, Darwin was finely attuned to the sensitive religious and social debate around him. Not only did he not want to upset this delicate intellectual and spiritual balance and get labeled as a crackpot, but he himself had not started his voyage as a complete non-believer. One can imagine the torment that he must have faced in those early days, when the evidence pointed to facts that flew in the face of deeply-held or familiar religious beliefs. One of the factors that dispossessed Darwin of his religious beliefs was the stark contradiction between the observation of a cruel and ruthless race for survival that he had often witnessed first hand, and the image of an all-knowing and benign God who kindly reigned over his creations. As the evidence grew to suggest a relationships between species and their evolution by the forces of natural selection that preserved beneficial characteristics, Darwin could no longer sustain two diametrically opposite viewpoints in his mind.

Opponents of evolution who want to battle the paradigm not from a scientific viewpoint (because they can't) but from a political one frequently raise a smokescreen and proclaim that evolution itself is too complex to be understood. The tricksters who propagate intelligent design further attest to the biochemical complexity of life and then simply give up and say that only an omniscient God (admittedly more complex than the systems whose complexity they are questioning) could have created such intricate beauty. The concept of a struggle for survival has also been hijacked by these armies of God who proclaim that it is this philosophy that would make evolution responsible for genocide, fascism and the worst excesses of humanity. This is a deeply hurtful insult to natural selection and evolution as only the most dogmatic believers can deliver. One thing that constantly amazes you about evolution is its sheer simplicity. Stripped down to its essentials, the "theory" of evolution can be understood by any school child.

1. Organisms and species are ruthlessly engaged in a constant struggle for survival in which they compete for finiteresources in a changing environment.

2. In this struggle, those individuals who are more adapted to the environment, no matter how slightly, win over other less adapted individuals and produce more offspring.

3. Since the slight adaptations are passed down to the offspring, the offspring are guaranteed to preserve these features and therefore are in a position to survive and multiply more fruitfully.

4. Such constant advantageous adaptive changes gradually build up and, aided by geological and geographical factors, lead to the emergence of new species

It's almost like a simple three-step recipe that when followed keeps on churning out culinary wonders of staggering complexity and elegance. In my mind the beauty of evolution and natural selection is two-fold; firstly, as Darwin emphasized, the slightest adaptation leads to a reproductive advantage. Such slight adaptations are often subtle and therefore sometimes can sow confusion regarding their existence; notice the debate between driver and passenger mutations in fields ranging from evolutionary biology to oncology. But the confusion should be ameliorated by the second even more striking fact; that once a slight adaptation exists, it is guaranteed to be passed on to the offspring. As Gregor Mendel hammered the mechanism for natural selection in place a few years after Darwin with his discovery of genetic inheritance, it became clear that not every one of the offspring may acquire the adaptation. The exact pattern may be complex. But even if some of the offspring acquire it, the adaptation is then guaranteed to confer reproductive fitness and will be passed on. This fact should demolish a belief that even serious students of evolution, and certainly laymen, have in the beginning; that there is something very uncertain about evolution, that it depends too much on "chance". The key to circumvent these misgivings is to realise the above fact, that while adaptations (later attributed to mutations) may arise by chance, once they arise, their proliferation into future generations is virtually certain. Natural selection will ensure it. That in my mind is perhaps Darwin's greatest achievement; he finally found a mechanism for evolution that guarantees its existence and progress. As for the struggle for survival, it certainly does not mean that it results in non-cooperation and purging of other individuals. As examples in the living world now document more than convincingly, the best reproductive fitness can indeed come about through altruistic leanings and cooperative behaviour.

Every one of these factors and facts was detailed and explained by Darwin in "The Origin of Species", one of the very few original works of science which remain accessible to the layman and which contained truths that have not needed to be modified in their basic essence even after a hundred and fifty years. It was readable even when I picked it up as a callow young college student. No one who approaches it with an open mind can fail to be taken with its simplicity, elegance and beauty. One of the most extraordinary things about Darwin and something that continues to stupefy is how right the man was even when he lacked almost all the modern tools that have since reinforced basic evolutionary ideas. As one of Darwin's intellectual descendants, the biologist E O Wilson says, it is frustrating for a modern biologist to discover an evolutionary idea through his work, and then go back a hundred and fifty years and discover that the great man had hinted at it in his book.

And yet as Darwin himself would have acknowledged, there is much in the book that needed to be modified, there was much that he could not explain. Darwin had no inkling of genes and molecular biology, nor could he come up with a convincing mechanism that explained the sheer age of the earth required for evolutionary processes to work their charm (the mechanism was found later with the discovery of radioactivity). The exact mechanism of passing on adapted characteristics was unknown. Major fossils of primates and humanoid ancestors had yet to be discovered. Quite importantly, random genetic drift which is completely different from natural selection was later discovered as another process operating in evolution. The development of viral and bacterial resistance in causing diseases like AIDS finally brought evolution to the discomfort of the masses. It was only through the work of several evolutionary biologists and geneticists that Darwin finally became seamlessly integrated with the understanding of life in the middle twentieth century. Genomics has now proven beyond a shade of doubt that we truly are one with the biosphere. But in the absence of all these developments, it is perhaps even more remarkable how many of Darwin's ideas still ring true.

There is another factor that shines through in "The Origin"; Darwin's remarkable modesty. One would have to search very hard in history to find a scientist who was both as great and as modest. Newton may yet be the greatest scientist in history, but he was nothing if not a petty, bitter and difficult man. Darwin in contrast was a symbol of kindly disposition. He doted on his children and told them stories. He loved and respected his wife even though their religious views gradually grew more distanced. His written correspondence with her was voluminous and fond. His correspondence with his collaborators, even those who disagreed, was cordial and decent. Never one for contentious public debates, he let his "bulldog" Thomas Henry Huxley fight his battles; one of them with Bishop Samuel Wilberforce ended in a famous showdown when the Bishop inquired whether it was through his father or mother that Huxley had descended from an ape, and Huxley countered that he would rather descend from an ape than from the Bishop. Darwin stayed away from these entertaining confrontations; as far as he was concerned, his magisterial work was done and he had no need for public glory. To the end of his life this kind and gentle man remained a wellspring of modest and unassuming wonder. His sympathetic, humane and sweet personality continues to delight, amaze and inspire reverence to this day.

In the later stages of his life Darwin became what he himself labeled as an agnostic but what we today would probably call an atheist. His research into the progression of life and the ruthless struggle that it engenders made it impossible for him to justify a belief in a paternal and loving deity. He was also disillusioned by popular conceptions of hell as a place where non-believers go; Darwin's father was a non-believer and yet a good doctor who treated and helped hundreds of human beings. Darwin simply could not accept that a man as kind as his father would go to hell simply for not believing in a version of morality, creation and life trotted out in a holy book. Probably the last straw that convinced Darwin of the absurdity of blind faith was the untimely death of his young daughter Annie who was his favourite among all the children. According to some accounts, after this happened, Darwin stopped even his cursory Sunday trips to church and was satisfied to take a walk around it while not at all minding his wife and children's desire to worship inside. The second fact is also in tune with Darwin's kind disposition; he admittedly had no problem reconciling the personal beliefs of other people with his conviction about their falsity. Darwin's tolerance of people's personal faith and his unwillingness to let his own work interfere in his personal life and friendships is instructive; to the end he supported his local parish and was close friends with a cleric, the Reverend John Innes. Darwin's example should keep reminding us that it is actually possible to sustain close human bonds while having radically different beliefs, even when one of these is distinctly true while the other one is fantasy. Nurturing these close bonds with radical scientific ideas that would change the world for ever, Charles Darwin died on April 19, 1882, a content and intellectually satisfied man.

To follow, nourish and sustain his legacy is our responsibility. In the end, evolution and Darwin are not only about scientific discovery and practical tools arising from them, but about a quest to understand who we are. Religions try to do this too, but they seem to satisfied with explanations for which there is no palpable evidence and which seem to be often contradictory and divisive. It is far better to imbibe ourselves with explanations that come from ceaseless exploration and constant struggle; the very means that constitute these explorations are then much more alluring and quietly fulfilling than any number of divergent fantasies that can only promise false comfort. And these means promise us a far more humbling and yet grand picture of our place in this world. Especially in today's age when the forces of unreason threaten to undermine the importance of the beautiful simplicity in the fabric of life that Darwin and his descendants have unearthed, we owe it to Charles Darwin to continue to be amazed at the delightful wonder of the cosmos and life. We owe it to the countless shapes and forms of life around us with whom we form a profoundly deep and unspoken connection. And we owe it to each other and our children and grandchildren to keep rationality, constructive skepticism, freedom and questioning alive.

LITERATURE ON DARWIN:

I don't often write about Darwin and evolution here for a simple reason; there is literally an army of truly excellent authors and bloggers who pen eloquent thoughts about these subjects and the amount of stuff published about him will fill up entire rooms. You could probably put together a thousand-page encyclopedia simply listing works on Darwin. His original work as stated above is still very readable. Every aspect of his life and work - the scientific, the psychological, the social, the political and the personal - has been exhaustively analyzed. I have certainly not sampled more than a fraction of this wealth of knowledge, but based on my interest in Darwin and selected readings, I can recommend the following.

For what it's worth, if you want to have the best overview of Darwin's life after he came home from his voyage on the Beagle, I think nothing beats the elegance of language and wit of David Quammen's "The Reluctant Mr. Darwin". Quammen has exhaustively researched Darwin's post-Beagle life and work, and no one I have come across tells the story with such articulate enthusiasm, fondness and attention to detail in a modest sized book.

Janet Browne's magisterial biography of Darwin is definitely worth a look if you want to get all the details of his life. Browne pays more attention to the man than the science, but her work is considered the authoritative work, and there are nuggets of eloquence in it.

As a student in high school I was inspired by Alan Moorehead's "The Voyage of the Beagle" noted above which combines an account of Darwin's life and voyage with beautiful and full page illustrations.

Geting to evolution now, there's an even bigger plethora of writings. Several books have captured my attention in the last many years. I don't need to extol the great value of any (and indeed, all) of Richard Dawkins' books. If you ask me which ones I like best, I would suggest "The Selfish Gene", "The Extended Phenotype", "Climbing Mount Improbable" and "The Blind Watchmaker". For a journey into our ancestral history, Dawkins' strikingly illustrated "The Ancestor's Tale" is excellent. Speaking of ancestral history, Neil Shubin's "Our Inner Fish" charts a fascinating course that details how our body parts come from older body parts that were present in ancient organisms. So does his recent book "The Universe Within". Shubin provides scores of interesting tidbits; for instance he tells us how hernias are an evolutionary remnant. Another great general introduction to evolution is Carl Zimmer's "Evolution"; Zimmer has also recently written excellent books on bacteria and viruses in which evolution plays a central theme.

No biologist- not even Dawkins- has had the kind of enthralling command over the English language as Stephen Jay Gould. We lost a global treasure when Gould died at age sixty. His books are relatively difficult to read and for good reason. But with a little effort they provide the most sparkling synthesis of biology, history, culture and linguistic exposition that you can ever come across. And all of them are meticulously researched. Out of all these I personally would recommend "Wonderful Life" and "The Mismeasure of Man", and if you want to challenge yourself with a really difficult unedited original manuscript written just before he died, "The Hedgehog, the Fox and The Magister's Pox". In general, pick up any Gould book and you would have access to an extraordinary writer and mind. His collections of essays - "Full House" and "Eight Little Piggies" for instance - are also outstanding.

I don't want to really write about books which criticize creationism since I don't beat that horse much, but if you want to read one book about the controversy that rips apart intelligent design proponents' arguments, read Ken Miller's "Finding Darwin's God" which makes mincemeat out of the usual "arguments from complexity" trotted out by creationists which are actually "arguments from personal incredulity". He also has a book covering the Dover Trial. I have only browsed it but it seems to be equally good read. What makes Miller a tough target for creationists (and puzzling for evolutionists) is that he is a devout Christian.

This is an updated and revised version of a post originally written on Darwin's 200th birthday.

The views expressed are those of the author(s) and are not necessarily those of Scientific American.

ABOUT THE AUTHOR(S)

Ashutosh Jogalekar

Ashutosh Jogalekar is a chemist interested in the history, philosophy and sociology of science. He is fascinated by the logic of scientific discovery and by the interaction of science with public sentiments and policy. He blogs at The Curious Wavefunction and can be reached at curiouswavefunction@gmail.com.

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